Method for creating at least one clearance in a sheathing that consists of shrink film and secures a stack of items arranged on a pallet, and shaping apparatus for carrying out the method

ABSTRACT

A method for creating at least one clearance in a sheathing consists of shrink film and secures a stack of items arranged on a pallet. The pallet has a top standing surface for the stack of items and a plurality of spaced bottom legs forming leg clearances. The sheathing engages under the legs in the region of the four outer edges of the pallet. At least one clearance is introduced into the sheathing region located between two legs. At least one clearance is intended to be created such that the sheathing region is first of all pulled away from the pallet in the still-hot state and is subsequently displaced upwards in the still-hot state, wherein the upwardly displaced sheathing region is then fixed in its upwardly displaced position by cooling. The invention also relates to a shaping apparatus for carrying out the method.

CROSS-REFERENCE TO RELATED APPLICATIONS AND CLAIM TO PRIORITY

This application is a continuation of U.S. patent application Ser. No.15/273,364, filed Sep. 22, 2016, which is related to patent applicationSer. No. 15/186,529.2 filed Sep. 23, 2015 in the European Patent Office,the disclosures of which are incorporated herein by reference and towhich priority is claimed.

FIELD OF THE INVENTION

The invention relates to a method for creating at least one clearance ina sheathing that consists of shrink film and secures a stack of itemsarranged on a pallet, wherein the pallet has a top standing surface as asupport for the stack of items and a plurality of bottom legs that arearranged in a manner spaced apart from one another, forming legclearances, and wherein the sheathing engages at least partially underthe underside of the legs arranged in the region of the four outer edgesof the pallet (undershrinking), and wherein at least one clearance isintroduced into the sheathing region located between two legs which arearranged in a row having at least two legs.

BACKGROUND OF THE INVENTION

In a Euro-pallet, a total of three rows of in each case three legs ofblock-like design are provided, wherein the three legs in a row areconnected together on the underside by a bottom board. With such aconfiguration, the sheathing engages under the underside of the twooutermost bottom boards. The standing surface usually consists of fivetop boards. Transverse boards can also be arranged between the legs andthe standing surface.

The undershrinking method is a method for load securing a stack of itemsarranged on a pallet. In the shrinking method, a shrink hood is usuallyused, which is pulled from above over the stack of items arranged on thepallet and is subsequently shrunk from top to bottom or from bottom totop. As a result, the stack of items is wrapped on the four sides andthe top side. In conjunction with a base sheet, it is also possible toprotect the stack of items on all sides. In the not-yet shrunk state,the shrink hood has a greater length than the stack of items includingthe pallet, and so, in the not-yet shrunk state, the shrink hoodprotrudes downwardly with respect to the underside of the pallet. In theundershrinking method, that edge of the shrink hood that protrudesdownwardly with respect to the underside of the pallet is heated andconsequently contracts under the pallet. As a result, maximum protectionand the best possible load stability are achieved.

For transport using industrial trucks, for example a forklift truck,clearances have to be introduced in the lower region in order to pick upthe pallet. These clearances are usually achieved by piercing thesheathing with the fork tips. A disadvantage is that the leg clearancesare not completely free of the sheathing. Therefore, the pallet isfrequently not accepted by automated high-bay warehouses, since theobligatory system capability test of the leg clearances between the legsreturns a negative result. Attempts have also been made to remove theentire undershrink and also side shrink in the region of the pallet fromthe region of the pallet side into which the fork tips of a forklifttruck are intended to be introduced. Although the leg clearances arecompletely free as a result, this results in significant impairment ofthe load stability.

SUMMARY OF THE INVENTION

It is the object of the invention to avoid the abovementioneddisadvantages and to specify a method with which a leg clearance or legclearances between the legs of a pallet can be rendered completely freeof the sheathing without the load stability and the protective action ofthe sheathing being reduced as a result.

This object is achieved in that at least one clearance is created suchthat the sheathing region is first of all pulled away from the pallet inthe still-hot state, that means after the shrinking of the sheathingregion, and is subsequently displaced upwards in the still-hot state,wherein the upwardly displaced sheathing region is then fixed in itsupwardly displaced position by cooling. Once the sheathing region hascooled sufficiently, it remains in this position. Consequently, the legclearance in question is completely free of the sheathing region sincethe sheathing region has been “laid” around the leg clearance inquestion. The still-hot state is understood as meaning the state inwhich the sheathing contracts on account of the heating because of itsrestoring forces and thus effects load securing through the transverseand longitudinal forces acting on the stack of items.

With the method according to the invention, the leg clearances can bereliably made available in this respect. The method according to theinvention can be integrated easily into the previous shrinking processand allows the production of durable sheathing. The method can be usedfor all pallet types and warehouses, wherein the load stability can beset as desired.

The upward displacement can take place as far as the region of thestanding surface of the pallet, preferably as far as slightly above thestanding surface of the pallet.

During the upward displacement of the sheathing region, the sheathingcan be pulled around the respective lower inner edge of the two legs.The inner edges are understood as being the mutually facing edges of thetwo legs.

The two legs can be directly adjacent. The two legs can alternativelyalso be the outermost legs of a row. If three legs are arranged in therow, the upwardly displaced sheathing region would thus extend over thecentral leg. If the pallet has for example five legs in a row, the twolegs can also be the second and fourth legs.

The sheathing can be fixed to the underside of the two legs beforeand/or after the sheathing region is pulled away from the pallet and/orbefore and/or after the sheathing region is displaced upwards.

The sheathing region can be pulled away and/or displaced upwards fromthe pallet such that the sheathing remains fixed to the underside of thetwo legs.

A shrink hood can be used as the sheathing.

It is appropriate for at least one subregion of the sheathing to befixed above the sheathing region from the outside in the horizontaldirection with respect to the pallet, at least in at least one regionclose to a leg clearance, preferably by pressure exertion, at leasttemporarily while the sheathing region is being pulled away and/ordisplaced upwards. In this way, an undesired half-moon formation isavoided in the region of the side shaped by means of the methodaccording to the invention.

In this case, at least the upwardly displaced sheathing region that isin the still-hot state can be displaced in the direction of the palletagain before cooling. In this way, the sheathing region is displacedcloser to the pallet again and can thus be connected to the sheathinglaid around the underside of the two legs enclosing the clearance(s),before the sheathing region and the sheathing set as a consequence ofcooling. This displacement in the direction of the pallet can take placefor example by means of a suitable device which is actively moved in thedirection of the pallet to this end. However, displacement can also takeplace by restoration as a consequence of a decreasing tensile forcewhich has been applied for example for the initial pulling of thesheathing region away from the pallet in the still-hot state.

Furthermore, the displacement at least of the upwardly displacedsheathing region that is in the still-hot state back in the direction ofthe pallet can take place to such an extent in the direction of thepallet before cooling that the stretched sheathing region and/or thosesubregions of the sheathing that respectively adjoin the sheathingregion laterally is/are pressed at least slightly at the rear against atleast one leg and/or the standing surface of the pallet. If thestretched sheathing region is pressed directly against the pallet insuch a procedure, the sheathing region sticks to the pallet in thecontact region after curing.

As a result of the displacement of the stretched sheathing region backin the direction of the pallet, that subregion of the sheathing thatadjoins the sheathing region laterally can be flapped over to form akind of fold which is located between the stretched sheathing region andthe pallet and points in the direction of the clearance to be created.The rear half of the fold is in direct contact with the leg and/or withthe standing surface of the pallet after pressure exertion, while theother half of the fold is in contact with the rear half of the fold andwith the stretched sheathing region displaced in the direction of thepallet.

As a result of the pressure exertion, good adhesive bonding of thesheathing region and/or of that subregion of the sheathing that adjoinsthe sheathing region laterally is achieved, such that the upwardlydisplaced cured sheathing region stretched in the manner of a portal isfixed securely and durably to the leg(s) and/or the standing surfaceand/or that subregion of the sheathing that adjoins the sheathing regionlaterally. As a result of the pressure exertion, additionalstabilization is achieved in this respect.

The invention also relates to a shaping apparatus for carrying out amethod for creating at least one clearance in a sheathing that consistsof a shrink film and secures a stack of items arranged on a pallet,wherein the pallet has a top standing surface as a support for the stackof items and a plurality of bottom legs that are arranged in a mannerspaced apart from one another, forming leg clearances, and wherein thesheathing engages at least partially under the underside of the legsarranged in the region of the four outer edges of the pallet, andwherein at least one clearance is introduced into the sheathing regionlocated between two legs which are arranged in a row having at least twolegs.

In a Euro pallet, a total of three rows of in each case three legs ofblock-like design are provided, wherein the three legs in a row areconnected together on the underside by a bottom board. With such aconfiguration, the sheathing engages under the underside of the twooutermost bottom boards. The standing surface usually consists of fivetop boards. Transverse boards can also be arranged between the legs andthe standing surface.

The undershrinking method is a method for load securing a stack of itemsarranged on a pallet. In the shrinking method, a shrink hood is usuallyused, which is pulled from above over the stack of items arranged on thepallet and is subsequently shrunk from top to bottom or from bottom totop. As a result, the stack of items is wrapped on the four sides andthe top side. In conjunction with a base sheet, it is also possible toprotect the stack of items on all sides. In the not-yet shrunk state,the shrink hood has a greater length than the stack of items includingthe pallet, and so, in the not-yet shrunk state, the shrink hoodprotrudes downwardly with respect to the underside of the pallet. In theundershrinking method, that edge of the shrink hood that protrudesdownwardly with respect to the underside of the pallet is heated andconsequently contracts under the pallet. As a result, maximum protectionand the best possible load stability are achieved.

For transport using industrial trucks, for example a forklift truck,clearances have to be introduced in the lower region in order to pick upthe pallet. These clearances are usually achieved by piercing thesheathing with the fork tips. A disadvantage is that the leg clearancesare not completely free of the sheathing. Therefore, the pallet isfrequently not accepted by automated high-bay warehouses, since theobligatory system capability test of the leg clearances between the legsreturns a negative result. Attempts have also been made to remove theentire undershrink and also side shrink in the region of the pallet fromthe region of the pallet side into which the fork tips of a forklifttruck are intended to be introduced. Although the leg clearances arecompletely free as a result, this results in significant impairment ofthe load stability.

It is the object of the invention to avoid the abovementioneddisadvantages and to specify an apparatus which allows a leg clearanceor leg clearances between the legs of a pallet to be completely freed ofthe sheathing without the load stability and protective action of thesheathing being reduced as a result.

This object is achieved in that, in order to carry out the method, atleast two shaping fingers are provided which are displaceable in thevertical direction for the upward displacement of the sheathing regionand are preferably also displaceable in the horizontal direction forpulling the sheathing region away from the pallet, preferablybeforehand. By way of the shaping apparatus, the sheathing region thatis for example still hot as a result of a preceding shrinking process isfirst of all pulled outwards away from the pallet and subsequentlydisplaced upwards by a vertical movement of the shaping fingers. In thisway, the sheathing region is stretched in the manner of a portal. Thisshape is retained by the sheathing region after cooling, such that thecorresponding leg clearance or the corresponding leg clearances is/arefreely accessible durably. During the upward displacement of thesheathing region, the sheathing is preferably pulled around therespective lower inner edge of each of the two legs, such that, as aresult, the undershrink is maintained in the two regions of thesheathing that adjoin the upwardly displaced sheathing region laterally,and as a result load securing is provided.

The two legs can be for example directly adjacent legs such that a legclearance is then freely accessible. If the two legs are the outermostlegs in a row, at least two leg clearances and also the end side and theunderside of the leg(s) located in between are freely accessible. Thesheathing can be fixed to the underside of the two legs before and/orafter the sheathing region is pulled away from the pallet and/or beforeand/or after the sheathing region is displaced upwards, oralternatively, the sheathing region can be pulled away and/or displacedupwards from the pallet such that the sheathing remains fixed to theunderside of the two legs.

The vertical displacement can be an exclusively vertical displacement.Of course, the shaping finger in question can also be displacedhorizontally during the vertical displacement, such as in a pivotingmovement, for example.

The shaping apparatus according to the invention represents an extensionof known shrink systems for full pallets through the automated freeforming of a leg clearance or of leg clearances of a pallet to ensurethe system capability for automated warehousing facilities, inparticular high-bay warehouses. The shaping apparatus can be integratedin a shrink machine.

As a result of the compact design, the shaping apparatus according tothe invention can be integrated easily into an existing shrinkingprocess or an existing shrink machine can be extended by a shapingapparatus. The shaping apparatus according to the invention isdistinguished by high variability. It is suitable for different palletformats, such as the Euro-pallet, the “industrial pallet” (EUR2) or the“Düsseldorf pallet” (EUR6), for example. If the shaping apparatus isintegrated into a shrink station, the shaping apparatus is preferablylocated outside the immediate heating region of the hot-air frame duringrest periods and during the undershrinking process, such that the heatinput is reduced as a result, cooling is possible and heating up of theshaping apparatus is kept as low as possible. An additional coolingsystem for the shaping apparatus is then not required. Of course, atleast one shaping apparatus can be assigned a cooling system. Such aconfiguration can be appropriate for example when the shaping apparatusis intended to be already displaced in the direction of the palletduring the ongoing undershrinking operation.

It is appropriate here for at least one shaping finger to be mounted soas to be pivotable about a pivot pin oriented parallel to the horizontaltravel path, such that, for shaping, this shaping finger is pivotableupwards and outwards by means of a drive. Preferably, the shapingapparatus has two shaping fingers that are each mounted so as to bepivotable about a pivot pin oriented parallel to the horizontal travelpath. In their rest position, the shaping fingers point towards oneanother and are pivoted outwards away from one another for shaping.Thus, the sheathing region is displaced upwards and in this waystretched in the manner of a portal, while the sheathing is stilllocated in its original position in the two regions laterally adjoiningthe sheathing region and thus still engages around the underside of thepallet. Thus, the corresponding leg clearance or the corresponding legclearances is/are freely accessible. At least one shaping finger that ismounted so as to be pivotable about a pivot pin oriented parallel to thehorizontal travel path is preferably oriented with respect to the palletsuch that the shaping finger is at a distance from the outer side of thepallet during pivoting and thus cannot come into contact with thepallet.

In addition, the shaping apparatus can have at least two shaping fingerswhich are displaceable in the horizontal direction to pull the sheathingregion away from the pallet. In such a configuration, these shapingfingers serve only to pull the sheathing region away, while the shapingfingers that are each mounted so as to be pivotable about a pivot pinoriented parallel to the horizontal travel path effect the upwardsdisplacement of the sheathing region.

At least one pivotably mounted shaping finger can be formed and/orarranged in such a way with respect to the shaping finger(s) that is/aredisplaceable only in the horizontal direction and is/are assigned to theshaping finger that this pivotably mounted shaping finger is not incontact with the sheathing region during the pulling away operation. Inthis way, the pulled-out sheathing region can be received reliably bythe pivotably mounted shaping fingers.

In this case, the shaping apparatus can have a guide and a drive for ahorizontal displacement and/or the shaping apparatus can have a verticalguide and a drive for a vertical displacement.

In order to grasp the sheathing region, the end of at least one shapingfinger can be configured as a tab and/or as a hook. The hook can be forexample an angled portion which is provided at the end of the shapingfinger in question and projects into the sheathing from below. By way ofthe tabs or hooks, the sheathing region can be pulled outwards away fromthe pallet. That side or face of a tab or hook that faces the pallet canalso be used as a pressing face. If, in the subsequently stretchedstate, the shaping apparatus is displaced horizontally again in thedirection of the pallet side that is oriented orthogonally to theconveying direction of the pallet, the shaping fingers press the not-yetcooled double-ply sheathing against the standing surface or the outerside of the leg of the pallet with their faces that face the pallet. Asa result, the stretched sheathing region and the adjoining sheathing aredisplaced closer to the pallet again and are connected on cooling to thesheathing laid around the leg, before said sheathing cures, such thatadditional stabilization is achieved as a result by the sheathing regionconnected to the adjoining sheathing and/or the pallet.

In the case of at least one shaping finger, at least one, preferablyeach, region that comes into contact with the sheathing and/or with thesheathing region is coated and/or provided with a non-stick and/orheat-resistant material. When a non-stick material is used, the frictionbetween the shaping finger and the sheathing is reduced such that thesheathing is not damaged. As a result of the use of a non-stickmaterial, sticking of the hot sheathing to the surfaces of the shapingfingers is also avoided. Thus, the surface energy on the shaping fingercompared with the hot sheathing is minimized by non-stick materials, andso surface wetting and an adhesive bond are avoided. Since the shapingapparatus is located outside of the heating region in its rest position,heating of the shaping apparatus, in particular of the shaping fingers,is reduced as far as possible, such that, as a result, the surfaceenergy and the adhesion tendency are likewise kept low. The use of aheat-resistant material is appropriate, since the sheathing is in thestill-hot state while the method is carried out.

The shaping apparatus cooperating with one side of a pallet can consistof two halves, wherein each half has at least one pivotable shapingfinger in each case and optionally also at least one shaping finger, andpreferably each half is constructed in a mirror-inverted manner andwherein preferably both halves are displaceable synchronously. Such aconfiguration is appropriate for example in the case of a pallet havingthree rows of legs, wherein, in such a case, the pallet conveyor, whichcan be for example a pull-over station conveyor or a shrink stationconveyor, also has three movement tracks adapted to the rows of legs ofthe pallet. A pull-over station conveyor is located upstream of a shrinkmachine, as seen in the transporting direction. Here, a sheathingconfigured preferably as a hood can first of all be pulled over. Ofcourse, a configuration in which pulling over and shrinking take placeat one location is also conceivable. A movement track can be for examplea chain track, a belt track or the like. One half of the shapingapparatus in this case creates a clearance in the left-hand legclearance and the other half of the shaping apparatus creates aclearance in the right-hand leg clearance. In this way, the sheathingregion is “laid” around the two leg clearances and sets in the tautposition on cooling. Consequently, the pallet is free both in the regionof the two leg clearances and at the end in the region of the middle rowof legs.

At least one shaping finger can be assigned a stop that limits thepivoting travel of this shaping finger, said stop extending parallel tothe horizontal travel path and in a manner protruding in the oppositedirection beyond the shaping finger(s) assigned to this shaping finger.During the pivoting movement, the stop thus projects into the contour ofthe pallet, i.e. into the leg clearance. If the stop comes into contactfor example with the leg of the leg clearance during the pivoting of theshaping finger, the pivoting movement is stopped.

In order to adapt the orientation of the shaping apparatus with respectto the pallet, an angle compensation element, preferably configured as avertically oriented peg, can be provided. In this way, the shapingapparatus is also able to be oriented with regard to a pallet arrangedin a non-optimal manner.

To fix the sheathing while the sheathing region is being pulled awayand/or displaced upwards with respect to the pallet, preferably in theregion of that side of the sheathing that is to be shaped, a fixingelement that is displaceable in the direction of the pallet can beprovided.

The invention also relates to a shrink machine comprising a hot-airframe which is movable vertically along a stack of items arranged on apallet and provided with a sheathing that consists of a shrink film, andalso at least one shaping apparatus according to one of the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

Exemplary embodiments of the invention that are illustrated in thedrawings are explained in the following text. In the drawings:

FIG. 1 shows a shrink station conveyor having a total of two shapingapparatuses according to the invention of a shrink machine,

FIG. 2 shows a shaping apparatus in the flapped-in and non-raised state(rest position),

FIG. 3 shows the shaping apparatus according to FIG. 2 in theflapped-out and raised state,

FIG. 4 shows the shaping apparatus in the rest position,

FIG. 5 shows the moving of the shaping apparatus up to the pallet,

FIG. 6 shows the pulling-away movement of the shaping apparatus,

FIG. 7 shows the shaping of the sheathing region,

FIG. 8 shows the pressure exertion operation, and

FIG. 9 shows the sheathing in the shaped state.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT(S)

In all of the figures, corresponding reference signs are used forcomponents that are identical or of the same type.

As illustrated in FIG. 1, the shrink machine comprises, inter alia, ashrink station conveyor, which is configured as a chain conveyor in theexemplary embodiment illustrated. The chain conveyor comprises fivechain tracks 1 in the exemplary embodiment illustrated. The first andthe second chain track 1 and the fourth and the fifth chain track 1 areeach arranged close together at a slight distance apart. The distancebetween adjacent chain tracks 1 is adapted to the formats of the pallet2 to be conveyed. By means of the chain conveyor, a pallet 2 which ispositioned thereon and on the top of which a stack of items is arranged,can be moved in the conveying direction (arrows 3). Usually, the twolongitudinal edges of the pallet 2 are oriented parallel to theconveying direction 3, while the two short end edges of the pallet 2 areoriented orthogonally to the conveying direction 3.

The shrink machine illustrated has a pallet lifting device 4 havinglifting rams 5, a blower module 6 and a total of two shaping apparatuses7. Not illustrated is the hot air frame, which is usually arrangedcentrally in the shrink machine. The two ends of the shrink stationconveyor are connected via suitable connection points to the furtherconveying technology or to other machine constituents, such as a hoodpull-over station, for example.

As can be gathered in particular from FIGS. 2 and 3, each pallet 2 sidethat is oriented orthogonally to the conveying direction 3 is assigned ashaping apparatus 7. Thus, one shaping apparatus 7 acts on the pallet 2side that is oriented orthogonally to the conveying direction 3 and theother shaping apparatus 7 acts on the opposite other pallet 2 side thatis oriented orthogonally to the conveying direction 3. Each shapingapparatus 7 consists of two halves, wherein one half is arranged in theregion between one outer chain track 1 and the middle chain track 1 andthe other half is arranged in the region between the middle chain track1 and the other outer chain track 1. The two halves of the shapingapparatus 7 acting on one pallet 2 side are constructed in amirror-inverted manner with respect to one another.

FIGS. 2 and 3 show a shaping apparatus 7 in detail. Each shapingapparatus 7 has a guide 8 and a drive (not illustrated). In this way,each shaping apparatus 7 can be displaced towards the pallet 2, and awayagain, from both sides as seen in the conveying direction 3. The guide 8is arranged parallel to and beneath the middle chain track 1. In theexemplary embodiment illustrated, the guide 8 is configured as a ballrail system. However, other configurations are also possible. It is alsoconceivable for each of the two shaping apparatuses 7 to be assigned aseparate guide 8. The shaping apparatus 7 interacting with the pallet 2side that is oriented orthogonally to the conveying direction 3 can thenbe displaced separately from the shaping apparatus 7 cooperating withthe other pallet 2 side that is oriented orthogonally to the conveyingdirection 3. For vertical lifting (arrow 9) for the shaping operationand for subsequent lowering after the shaping operation, a verticalguide having a drive is provided, which comprises a cylinder 10 in theexemplary embodiment illustrated. By means of the cylinder 10, the upperpart of the shaping apparatus 7 is vertically displaceable. The verticalguide is configured as a ball rail system in the exemplary embodimentillustrated and is arranged next to the cylinder 10.

In order to compensate for angular deviations in the orientation of thepallet 2, each shaping apparatus 7 has an angle compensation element 11.The angle compensation element 11 is a vertically oriented peg on whichthe shaping apparatus 7 is arranged in a rotatably mounted manner. Bymeans of a spring, the shaping apparatus 7 is kept in the position whichcorresponds to an optimal orientation of the pallet 2 on the chaintracks 1. In the optimal orientation, the side edges of the pallet 2 areoriented orthogonally or parallel to the conveying tracks 1.

When the shaping apparatus 7 is moved up to the pallet 2, the pallet 2can be set down on the chain tracks 1 or raised by means of the liftingrams 5. If the pallet 2 has not been set down optimally on the chaintracks 1, the orientation of the pallet 2 is generally maintained whenit is raised by way of the lifting rams 5. Any angular error would thuscontinue to exist.

When the shaping apparatus 7 is moved up to the pallet 2, the shapingapparatus 7 is oriented automatically with respect to the pallet 2. Ifthe pallet 2 is not oriented optimally with respect to the chain tracks1, when contact is made with the pallet 2, the shaping apparatus 7 isrotated by the pallet 2, counter to the force of the spring, into theposition which corresponds to the orientation of the pallet 2.

In the rest state, as illustrated in FIG. 4, each shaping apparatus 7has been lowered beneath the conveying level within the shrink stationconveyor. In the exemplary embodiment illustrated, each half of ashaping apparatus 7 comprises three upwardly directed shaping fingers 12and 12.1, the respective ends of which are configured as a tab and/or asa hook 24, 24.1. By means of the tabs and/or hooks 24, 24.1, a sheathing17, as will be described in the following text, can be grasped, pulledout, shaped and additionally pressed against the side of the pallet 2 inparticular while the still-hot sheathing 17 sets by cooling, as isillustrated in FIG. 8. The contact regions of the shaping fingers 12 and12.1 can be coated or provided with a non-stick and/or heat-resistantmaterial 27 at least in the regions that come into contact with thesheathing 17 and/or with the sheathing region 18.

As can be gathered in particular from FIGS. 5, 6 and 9, the non-stickand/or heat-resistant material 27 extends at least in the region of thatsurface of each hook 24.1 that faces towards and away from the pallet 2and in the region of the side face of each shaping finger 12.1, saidface pointing upwards in the position illustrated in FIGS. 5, 6 and 9.However, it is also quite possible for the non-stick and/orheat-resistant material 27 to also extend at least in the region of thatsurface of each hook 24 that faces away from the pallet 2 and in theregion of the side face of each shaping finger 12, said face pointingupwards in the position illustrated in FIGS. 5 and 6.

Each half of the shaping apparatus 7 has two shaping fingers 12 whichare displaceable in the horizontal direction in order to pull thesheathing region 18 away from the pallet 2. The third shaping finger ofeach half, namely the shaping finger 12.1, is mounted in a pivotablemanner, as can be seen for example in FIGS. 3 and 9. To this end, theshaping finger 12.1 is assigned a drive 13 such that the shaping finger12.1 is displaceable about the pivot pin 14. As can be gathered fromFIGS. 2 and 3, the shaping finger 12.1 is configured in such a way withrespect to the two shaping fingers 12 which are assigned to this shapingfinger 12.1 that this shaping finger 12.1 is not in contact with thesheathing region 18 during the pulling away operation.

Each movable shaping finger 12.1 is assigned a stop 15 which allowsautomatic fitting into the corners of the leg clearances 16 of thepallet 2, regardless of the format of the pallet 2. During the pivotingmovement, the stop 15 projects into the contour of the pallet 2, i.e.into the leg clearance 16. If the stop 15 comes into contact with theleg of the leg clearance 16 during the pivoting of the shaping finger12.1, the pivoting movement is stopped.

In FIGS. 4 to 9, the profile of the sheathing 17 and of the sheathingregion 18 is indicated by dashed lines. The sheathing region 18 isunderstood as being that region of the sheathing 17 which is located infront of the leg clearance 16 of the pallet 2 without the methodaccording to the invention being carried out, said leg clearance 16being intended to be made accessible by a clearance in the sheathing 17.For clearer illustration, the stack of items arranged on the pallet 2 isnot illustrated. The vertical extent of the sheathing 17 upwardly beyondthe pallet 2 is therefore only indicated. The shrink station conveyor isalso not illustrated.

FIGS. 4 to 9 illustrate a pallet 2 which has three rows consisting of ineach case three legs 19, 20, 21 of block-like design, wherein the threelegs 19 and 20 and 21 in a row are connected together on the undersideby a bottom board 22. The sheathing 17 engages in this respect aroundthe underside of the two outermost bottom boards 22 and the twooutermost ends of the bottom board 22 connecting the legs 20. On the topside, the pallet 2 has a standing surface 23 which consists of five topboards. It is also possible for transverse boards to be arranged betweenthe legs 19, 20, 21 and the standing surface 23. For clarity, theabove-described components of the pallet 2 are labelled only in FIG. 4.

In the exemplary embodiment illustrated in FIGS. 4 to 9, the two legsare the outermost legs 19, 21. In this respect, the sheathing region 18to be displaced upwards extends over the middle leg 20 such that boththe leg clearance 16 between the two legs 19, 20 and the leg clearance16 between the two legs 20, 21 is completely free of the sheathingregion 18 after the method according to the invention has been carriedout.

As already described above, each shaping apparatus 7 consists of twohalves, wherein each half is assigned to a leg clearance 16 and has theabove-described two shaping fingers 12 and the shaping finger 12.1 tocreate a clearance. A view of the short side of the pallet 2 (as seen inthe conveying direction 3) is illustrated in the respective left-handhalf of FIGS. 4 to 9 and a view of the long side of the pallet 2(parallel to the conveying direction 3) is illustrated in the right-handhalf of FIGS. 4 to 9.

In the method illustrated in the figures, first of all a pallet 2 isconveyed into the shrink machine and stopped. Subsequently, the pallet 2is raised for undershrinking by means of the pallet lifting device 4,which has lifting rams 5 that are displaceable in a manner correspondingto the size of the pallet 2. After raising, the undershrinking of thelower periphery of the sheathing 17 is carried out. In the meantime, thetwo shaping apparatuses 7 are located outside the heating region intheir rest position, as is illustrated in FIG. 4.

After completion of undershrinking, the pallet 2 is lowered to a lowerheight, but not set down. If desired, the undershrink created in theraised state can additionally be secured at the outer periphery of thepallet 2 by means of pressure rams 26. By means of the pressure rams 26,which are arranged between the first and the second chain track 1 andthe fourth and the fifth chain track 1, respectively, the lowerperiphery of the sheathing 17 and thus the undershrink is pressedagainst the underside of the pallet 2 in the region of the sidesoriented parallel to the conveying direction 3. For the movement of thepressure rams 26, a mechanical coupling can be provided for examplebetween the pressure rams 26 and the movement of the pallet liftingdevice 4. Alternatively, the pressure rams 26 can also be embodied in apower-driven manner.

Subsequently, the shaping apparatuses 2 are moved up to the pallet 2from both sides. This takes place on the one hand by a horizontalmovement (arrow 3). Furthermore, the shaping apparatuses 7 are raised inthe direction of the arrow 9. This is illustrated in FIG. 5. During thehorizontal displacement, the shaping fingers 12, 12.1 are still locatedbeneath the plane of the bottom boards 22 of the pallet 2, such that theshaping fingers 12, 12.1 can be moved within the contour of thesheathing 17.

The shrinking process can in this case be continued by moving theheating frame vertically upwards. The shaping apparatuses 7 moved up tothe pallet 2 are therefore not located in the direct heating zone of thehot-air frame in their position moved up to the pallet 2.

In FIG. 6, the shaping fingers 12, 12.1 have already been raised to suchan extent that the hooks 24, 24.1 are located above the lower peripheryof the sheathing 17 and thus within the sheathing 17, such that thehooks 24, 24.1 of the shaping fingers 12, 12.1 engage behind thesheathing 17 that is still hot and soft from undershrinking. The shapingapparatus 7 and thus the shaping fingers 12, 12.1 are subsequently movedaway from the pallet 2 by the drive assigned to the guide 8, such that,as a result, the sheathing region 18 grasped by the hooks 24, 24.1 ispulled away from the pallet 2 in the still-hot state. This isillustrated in FIG. 6.

Subsequently, the sheathing region 18 is displaced upwards in thestill-hot state. This is illustrated in FIG. 7. To this end, the shapingfingers 12.1 having the hooks 24.1 are pivoted upwards and outwards in apivoting movement about their pivot pins 14. In this case, the sheathing17 is pulled around the respective lower inner edge of the two legs 19,21, i.e. around the right-hand lower inner edge of the leg 19 and aroundthe left-hand lower inner edge of the leg 21, in the exemplaryembodiment illustrated.

During this pivoting movement, the sheathing region 18 is also pulledalong and pulled upwards. The sheathing region 18 is, in the process,displaced outwardly in the direction of the outwardly directed corner ofeach leg clearance 16. By way of the two pivoted-up shaping fingers 12.1of the shaping apparatus 7 acting on a common side of the pallet 2, thesheathing region 18 is stretched in this way. In order to limit thepivoting movement, each shaping finger 24.1 is assigned a stop 15. Sincethe stop 15 projects into the contour of the pallet 2, i.e. into the legclearance 16, at least with its front end, the stop 15 comes intocontact with the leg of the leg clearance 16 while the shaping finger12.1 is being pivoted, such that the pivoting movement is stopped uponcontact.

The shaping fingers 12, 12.1 having the respectively associated tab 24,24.1 are in this case located outside the contour of the pallet 2, i.e.at a distance from the outer side of the leg 19, 20, 21, such that thedeformed sheathing region 18 is “laid” from the outside around the legclearance 16 in question and, in the exemplary embodiment illustrated inFIGS. 4 to 9, around the two leg clearances 16. In the stretched state,each shaping apparatus 7 is displaced horizontally again in thedirection of the pallet 2 side oriented orthogonally to the conveyingdirection 3 of the pallet 2. Since the two shaping fingers 12.1 of ashaping apparatus 7 are longer than the four shaping fingers 12 of thisshaping apparatus 7 and thus protrude with respect to the shapingfingers 12, as seen in the direction of the pallet 2, the shapingfingers 12.1 come into contact, as a result of the horizontal movement,with the standing surface 23 or the outer side of the leg 19, 20, 21located in the travel path, with their hook 24.1 face that faces thepallet 2. To this end, the face of each hook 24.1 that faces the pallet2 is, inter alia, preferably coated with the non-stick and/orheat-resistant material 27, as described above with respect to FIGS. 5and 6.

By way of the hooks 24.1, the not-yet cooled double-ply sheathing 17 ispressed against the standing surface 23 or the outer side of the leg 19,20, 21 of the pallet 2, as is illustrated in FIG. 8. As a result of thehorizontal movement, the stretched sheathing region 18 and the adjoiningsheathing 17 are displaced closer to the pallet 2 again and areconnected on cooling to the sheathing 17 laid around the leg 19, 20, 21,before said sheathing 17 cures, such that additional stabilization isachieved as a result by the sheathing region 18 connected to theadjoining sheathing 17 and/or the pallet 2. The angle compensationelement 11 acts during this pressure exertion operation.

In the taut position, the sheathing region 18 then sets upon cooling. Asa result, the leg clearance 16 in question is durably completely free ofthe sheathing region 18. As a result of the stretching, the legclearances 16 under the pallet 2 are completely freed.

If desired, the sheathing 17 can be additionally fixed on the two sidesto be shaped, which, in the exemplary embodiment illustrated, are theshort end sides of the pallet 2, by a fixing element 25 that isdisplaceable in the direction of the pallet 2 and is configured in theform of a pin, while the sheathing region 18 is being pulled awayoutwards and/or while the sheathing region 18 is being displacedupwards. By means of the fixing element 25, the sheathing 17 is pressedagainst the pallet 2. As a result of this end-side fixing, undesiredhalf-moon formation is avoided.

In the exemplary embodiment illustrated, the middle chain track 1consists of two spaced-apart chains that extend in parallel. The fixingelement 25 is located between the two chains of the middle chain track1. Thus, the fixing element 25 acts approximately at the level of thestanding surface 23 or a little lower, in the middle of the pallet 2. Inthe exemplary embodiment illustrated, the fixing element 25 is displacedby a pivoting movement from its rest position illustrated in FIG. 1, inwhich it does not project out of the plane of the chain conveyor, intoits fixing position. The pivot pin and the associated drive of thefixing element 25 can be constituent parts of the chain conveyor.However, it is also quite possible for the pivot pin and the associateddrive of the fixing element 25 to be constituent parts of the shapingapparatus 7.

Alternatively, the fixing element 25 can be located laterally at a shortdistance from the middle chain track 1. It does not then act exactly onthe middle of the pallet 2, if the pivoting plane of the fixing element25 is parallel to the axis of the chain track 1 and the conveyingdirection 3. However, if the pivoting plane of the fixing element 25 isnot parallel to the axis of the chain track 1 and the conveyingdirection 3, contact is also possible in the middle of the pallet 2 inthis case. Regardless of the orientation of the pivoting plane of thefixing element 25, the fixing element 25 acts on the pallet 2approximately at the level of the standing surface 23 or a little lower.

It is of course also possible for a respective fixing element 25 to belocated on each side of the middle chain track 1, such that thesheathing 17 is pressed against the pallet 2 at two locations in thisway.

After completion of the shrinking process, the forming fingers 12.1 arepivoted back downwards again. This situation is illustrated in FIG. 9.As can be gathered from FIG. 9, the shaping apparatuses 7 have alreadybeen lowered again and moved outwards out of the heating region of theshrink machine in this illustration. If pressure rams 26 have been used,these are released when the pallet 2 is set down and the pallet 2 cansubsequently be conveyed away.

Of course, it is also possible for only one shaping apparatus 7 to beprovided, such that in this respect a clearance can be introduced intothe sheathing 17 only on one side.

1. A method for creating at least one clearance in a sheathingcomprising a shrink film for securing a stack of items arranged on apallet, wherein the pallet has a top standing surface as a support forthe stack of items and a plurality of bottom legs arranged in a mannerspaced from one another to form leg clearances, and wherein thesheathing is arrayed along a bottom of the pallet and engages at leastpartially under the underside of the legs arranged in a region of fourouter edges of the pallet, and wherein at least one of the legclearances is located in a sheathing region located between two legswhich are arranged in a row, the method comprising the followingsequential steps a) providing a shaping apparatus comprising a pluralityof pivotable fingers having ends for grasping the sheathing; b)shrinking the shrink film by heating to a hot state; c) positioning thefingers proximate the film in the sheathing region; d) pulling thesheathing region away from the pallet while the sheathing region is inthe still-hot state by moving the fingers away from the pallet; e)displacing the sheathing region upwardly while the sheathing region isin the still-hot state by pivoting the fingers upwardly; and f) fixingthe sheathing region in its upwardly displaced position by cooling. 2.The method of claim 1, wherein during the displacing step, the sheathingregion is displaced upwardly to the top standing surface.
 3. The methodof claim 1, wherein during the displacing step, the sheathing region isdisplaced upwardly above the top standing surface.
 4. The method ofclaim 1, wherein during the displacing step, the sheathing is pulledaround respective lower inner edges of the two legs.
 5. The method ofclaim 1, wherein the two legs are directly adjacent or are the outermostlegs of the row.
 6. The method of claim 1, wherein the sheathing isfixed to an underside of the two legs before and/or after the pullingstep, and/or before and/or after the displacing step.
 7. The method ofclaim 1, wherein the sheathing remains fixed to the underside of the twolegs during the pulling and/or displacing step.
 8. The method of claim1, wherein a shrink hood is used as the sheathing.
 9. The method ofclaim 1, wherein at least one subregion of the sheathing is fixed abovethe sheathing region from an outside in a horizontal direction withrespect to the pallet.
 10. The method of claim 1, wherein at least onesubregion of the sheathing is fixed above the sheathing region from anoutside in a horizontal direction with respect to the pallet byapplication of pressure during the pulling and/or displacing step. 11.The method of claim 1, further comprising the step of displacing thesheathing region in the direction of the pallet before the fixing step.12. The method of claim 11, wherein the step of displacing the sheathingregions in the direction of the pallet involves pressing the sheathingregion against at least one leg and/or the top standing surface of thepallet.
 13. The method of claim 1, wherein the ends of the fingerscomprises hooks for grasping and engaging the sheathing.
 14. The methodof claim 1, wherein the fingers are coated or provided with a non-stickand/or heat-resistant material.
 15. A method for sheathing a pallet withat least one clearance, comprising the steps of: a) providing asheathing apparatus including a shrink film positioning and heatingassembly, and a shaping apparatus comprising a plurality of pivotablefingers having ends engageable with shrink film; b) providing a pallethaving a top standing surface as a support for a stack of items and aplurality of bottom legs arranged in a manner spaced from one another toform leg clearances; c) providing a supply of shrink film; d)positioning the pallet in operable association with the shrink film sothat the film is arrayed along a bottom of the pallet and engages atleast partially under the underside of legs arranged in a region of fourouter edges of the pallet, and wherein at least one of the legclearances is located in a sheathing region located between two adjacentlegs; e) shrinking the shrink film by heating to a hot state; f)positioning the fingers proximate the film in the sheathing region; g)pulling the sheathing region away from the pallet while the sheathingregion is in the still-hot state by moving the fingers away from thepallet; h) displacing the sheathing region upwardly while the sheathingregion is in the still-hot state by pivoting the fingers upwardly towardthe pallet; and i) fixing the sheathing region in its upwardly displacedposition in engagement with a bottom of the pallet by cooling andthereby creating a clearance.
 16. The method of claim 15, wherein theends of the pivotable fingers comprises hooks for grasping and engagingthe sheathing.
 17. The method of claim 15, further comprising the stepof displacing the sheathing region in the direction of the pallet beforethe fixing step.
 18. The method of claim 17, wherein the step ofdisplacing the sheathing regions in the direction of the pallet involvespressing the sheathing region against at least one leg and/or the topstanding surface of the pallet.
 19. The method of claim 15, wherein thefingers are coated or provided with a non-stick and/or heat-resistantmaterial.
 20. The method of claim 15, wherein the fingers comprises afirst finger and a second finger configured to engage the shrink filmduring the step of pulling the sheathing region away from the pallet,and a third finger configured to engage the shrink film during the stepof pulling the sheathing region away from the pallet.